Throat length ?

Would this measurement give me my throat length if I seat my bullets to just touch the lands. Measured base of case to ogive with a comparator ( ogive is just touching lands) 2.927. My cases measure 2.615 after trimming. 2.927-2.615 = .312. Is .312 my throat length. This should give me the length from the top of the case mouth to the lands since the ogive of my bullet is just touching the lands.

To many unknown factors, it will get you close but not really, for one, the clearence between where your brass neck ends verses how deep the neck was cut in the chamber. But knowing the exact freebore is for why, if the bullet has plenty of neck depth and its touching the land or where ever you want it, the freebore is about right. Unless your trying to order another reamer and you need to tell the manufacturer what freebore you want so it matches your current chamber. What is the reason your trying to fiquire your exact throat length?

To many unknown factors, it will get you close but not really, for one, the clearence between where your brass neck ends verses how deep the neck was cut in the chamber. But knowing the exact freebore is for why, if the bullet has plenty of neck depth and its touching the land or where ever you want it, the freebore is about right. Unless your trying to order another reamer and you need to tell the manufacturer what freebore you want so it matches your current chamber. What is the reason your trying to fiquire your exact throat length?

Best of Luck

I am having the gun rebarreled, the gunsmith says his reamer has a 0 throat. I am assuming 0 throat means the reamer is to exact Sammi specs. 2.927 is as far as I can seat the bullets out and it to still function through the mag box. It also leaves enough room in the case for the slower powder that I want to use. I made two dummy rounds with the bullets seated at my desired length and will ship them with the rifle.

That is correct your smith will cut the throat after he is done with the chamber. I like the dummy rounds to be unfired just to make sure there is no resistence sliding them in that new tight chamber because they are the guage to measure the throat. You would be suprised how many times a fired round won't go in the new chamber.